The question I hear more than any other: "Will my Glowforge Aura engrave metal?"
If you run a small laser shop, you probably have a version of this conversation once a month. A customer sends a photo of a stainless steel tumbler and says, "Can you put our logo on this?" If you're smart, you ask follow-up questions first. I wasn't always smart.
My name is Derek, and I've been handling custom laser cutting and engraving orders for 7 years. I've personally made (and documented) 31 significant mistakes, totaling roughly $6,800 in wasted material, rework, and expedited shipping. Now I maintain our team's checklist so the next person doesn't have to learn this the expensive way. The most expensive mistake started with the exact question above.
That mistake wasn't a bad tool. It was a bad mental model. I assumed that because the Glowforge Aura laser cutter is called a "laser cutter and engraver," it should handle whatever I threw at it. It doesn't. And honestly, it shouldn't.
Why the Glowforge Aura craft laser is not a fiber galvo laser
Here's the part that took me two years to fully accept: "laser" is a category, not a specific tool. A bandsaw and a chainsaw both cut wood, but they're not interchangeable. Same idea here.
The Glowforge Aura craft laser is a desktop CO2 laser. It's designed for craft materials. CO2 lasers emit at a 10.6 µm wavelength. That wavelength is absorbed beautifully by wood, acrylic, leather, paper, fabric, and coated or painted surfaces. This is why the Glowforge is honestly great for makers, schools, and small businesses that work with those materials.
Bare metal is a different story. Most bare metals reflect that CO2 wavelength. The beam hits the surface and bounces off instead of coupling into it. It's not really a power problem. You could turn the power up and you'd still get a faint mark on some metals (or damage the optics on others). The problem is wavelength, not wattage.
A fiber galvo laser, on the other hand, operates around 1.06 µm. That wavelength is absorbed by metals, which is why fiber lasers are the default for marking and engraving stainless steel, aluminum, brass, and other metal parts. "Galvo" refers to the mirrors that steer the beam at high speed. It's a completely different machine, with a different laser source and different optics.
The ZnSe lens confusion
Once I understood that, I went down a lens rabbit hole. A customer asked if I'd tried a ZnSe laser lens. Zinc selenide is used in CO2 laser optics precisely because it transmits at 10.6 µm. So yes, if your Glowforge uses CO2, you have a ZnSe lens (or similar) in the optical path. A replacement ZnSe lens won't turn that CO2 beam into a fiber laser. It can improve things if your current lens is dirty or damaged, but it cannot change the wavelength. I do not care how fancy the lens is—it can't change the wavelength.
Someday someone will sell the "universal laser lens" myth. Don't buy it.
What that misunderstanding actually costs
Let me put a dollar amount on this. In 2021, we took a $3,200 order for 120 brushed steel tags with an engraved logo. I knew I should test the settings on a scrap piece first. But the customer confirmed the order on a Tuesday morning and wanted the proofs by Thursday. Under time pressure, I skipped the test.
Actually, let me be more honest. I didn't "skip" the test. I convinced myself it would be fine because the logo was high-contrast and the tags were "engravable steel." (Turns out "engravable steel" is a marketing term, not a physical guarantee. Mental note: check the metal before promising anything.) We set up the Glowforge, positioned the first tag, and hit Start.
I hit "Start" and immediately thought, Did I just ruin 120 tags? The beam traced the logo across the metal. It left a faint, scratch-like mark that wiped off with a dry rag. Not engraved. Not even close. So, yeah. That one hurt.
That error cost us $540 in scrap tags, $110 in rush shipping for replacement blanks, and the better part of a day re-testing. The customer stayed with us—actually, they were more forgiving than I deserved—but the real damage came later. Every time I engraved another metal job, I second-guessed myself. That hesitation cost more time than the mistake itself.
There was also a pattern. We didn't have a formal material approval process. The third time we burned a part that looked fine in the design file but wrong in reality, I finally created a pre-flight checklist. I should have done that after the first mistake.
The hidden cost is the one nobody writes on the invoice: credibility. If you tell a customer you can engrave their metal product and the result wipes off with a rag, they don't remember the wavelength excuse. They remember that you didn't know your own equipment. That's hard to come back from.
And for anyone who thinks it's just a file problem: yes, file resolution matters, but it won't save you here. A 300 DPI source file, the standard for commercial print work, is not going to make a CO2 beam get absorbed into bare steel. It will just give you a beautiful, perfectly detailed version of almost nothing.
The fix is simpler than you think
Here's what I'd tell someone buying a laser for a small business. I'd say it with more calm now, because I've burned the "it should just work" phase out of my system.
- Choose the machine for the material you actually work with. If you cut and engrave wood, acrylic, leather, paper, fabric, or coated metal, a Glowforge Aura craft laser is a great starting point. If you engrave bare metal, save up for a fiber galvo laser or send those jobs to a shop that has one. This isn't a knock on either machine. It's a boundary, and boundaries make work predictable.
- Use laser cut templates and tested settings. I used to design everything from scratch. Now I start from templates whenever possible—especially for cutting. A good template comes with a test file, material notes, and power/speed suggested ranges. It won't tell you what your exact lens or batch of material will do, but it removes the "I'll just guess" stage that caused most of my early failures.
- Label your optics. Not literally every lens, but a label. ZnSe laser lenses are for CO2 machines; fiber laser lenses are different. If you have both types of equipment in your shop, don't mix them. I'd argue this alone saved us from one expensive mistake.
- Make a pre-flight checklist and actually use it. Material type, thickness, condition, power, speed, focus, lens check, test cut. If you don't have a process, the same mistake will find you again.
So glad I eventually did this. We sent the next metal engraving job to a local metal finishing shop with a fiber galvo. They charged a fair price, hit the deadline, and the customer never knew we didn't own the right laser. That's the professionalism that matters.
The most trustworthy thing a vendor can say is, "This isn't our strength—here's who can do it better." I'd rather work with a specialist who knows their limits than a generalist who overpromises.
I have mixed feelings about the "craft laser" name. On one hand, it captures the accessibility that makes Glowforge unique. On the other, it can sound like a toy when it's really a serious tool for a specific range of materials. Part of me wants everyone to understand that before they buy. Another part knows that most people learn by making the same mistake I did. My hope is that this article saves you the expensive version of that lesson.
The Glowforge Aura isn't a fiber galvo laser. It doesn't have a ZnSe lens that can magically make it one. It's a craft laser with a real specialty. The sooner you accept that boundary, the more money you'll save—and the better your reputation will be.
